The present invention relates to a cutter roller and, more particularly, to a cutter roller provided with spraying nozzles each of which are individually arranged in a nozzle holder, with each nozzle holder being in communication with a connecting duct for a spraying liquid and a spray liquid supplied to the respective nozzles being controlled by forces acting upon the cutter during a cutting operation.
In, for example, German Pat. No. 3,302,103, a cutter roller provided with spraying nozzles is proposed wherein each nozzle is individually located in a nozzle holder, with the nozzle holder being connected to a connecting duct for spraying a liquid. During a normal operation of the cutter roller, the nozzle holder is connected to a shut-off valve which is always open but which, after having completely removed the spraying nozzle, automatically assumes a closed position in its liquid compressor.
In the above proposed construction, the spraying nozzle is positioned with a rear cylindrical section butting against an inhibiting element which is maintained in an open position in a longitudinal direction of the spraying nozzle against a resetting force of a compression spring, whereby the compression spring is supported on a front face thereof which faces away from the inhibiting element against a counter bearing which is permanently connected to the nozzle holder. A cartridge-shaped or cylindrical nozzle connector provided with an external thread, is threadably secured in a boring in a helix or similar manner and, in conjunction with the spraying nozzle, the shut-off valve forms a complete armature-type structural component which also can be exchanged.
By virtue of the fact that each spraying nozzle in the above described arrangement is correlated to a shut off valve which automatically operates, it is ensured that, in the event the spraying nozzle is not deflected, none of the spray liquid can escape from the respective duct openings. The automatic operating shut off valve is always in a state of operational readiness and becomes instantly operative in the event that any of the spraying nozzles may, for example, be broken or displaced out of their mounting. In such situations, the inhibiting or blocking element immediately closes the duct which is correlated to the respective spraying nozzle so that it is ensured that the spray liquid can not escape without having been used. This proposed construction is not expensive and, when compared to usual constructions, it provides an arrangement whereby the cutter roller does not have to be changed and the nozzle holder does not have to be welded in place but rather can be threadably inserted thereby facilitating the very quick change of the nozzle if such becomes necessary. Moreover, the components of the proposed arrangement are not exposed to any thermal stress.
In, for example, German No. DE-GM 79 17 606, a further spraying nozzle for cutter rollers is proposed which includes a nut-type housing which has a centrally-drilled hole on a water outlet side thereof and a collecting bore on the water inlet side which can be threadably inserted into a duct. A fitting in which a hole has been provided is provided on the water side and is pressed inside the collecting bore and a spray chamber is located between the central bore and the fitting. This arrangement provides a feasible way of suppressing dust by efficient nozzles as well as resulting in a reduction in time and costs when the roller is either to be repaired or during a down time necessary for cleaning the water nozzles.
In EP-PS No. 0 010 534, a device for cooling a cutting tool of a cutting machine at a cutting face as well as for suppressing dust is proposed with the cutting tool including at least one rotating cutting head on an articulated cutting arm of a cutting machine whereby the cutters are only periodically in contact with the workpiece to be cut. A control system is proposed which only releases a supplying of the cooling medium to the nozzle during the actual time when the cutter nozzles are in operation which are correlated to the respective nozzles. By such an arrangement, the water which is used as the cooling medium is to be used without adding any air whereby the cutter shaft o the cutter supported in the cutter holder in such a manner that it can be axially moved and is spring mounted against the cut and the control of the supply of the cooling medium is effected by a pushing movement of an admission valve of the cutter holder. The cutter holder is provided with a radially projecting shoulder which operates in conjunction with a tappet operable to open the valve An operating means for the valve body includes a sealing piston equipped with a projection which is adapted to effectively operate upon the valve body.
A construction comparable to the last proposed arrangement is also disclosed in Canadian Pat. No. 1,126,766; however, the proposed construction is extremely expensive and is hardly suitable for uninterrupted operation during rough mining conditions.
The air underlying the present invention essentially resides in providing an improved cutting roller having a plurality of spray nozzles each of which is arranged individually in a nozzle holder, with each nozzle holder being correlated to a connecting duct accommodating a spray liquid and supplying the spray liquid to the respective spray nozzles, with the supply being controlled in response to forces acting upon the respective cutter when carrying out a cutting operation. By virtue of the features of the present invention, it is possible to take into account the stresses which develop at the respective cutter during the cutting operation and utilizing the same at least to control an opening of a supply of the spray liquid to a spraying nozzle.
In accordance with advantageous features of the present invention, a cutter roller with spraying nozzles is provided wherein the nozzle holder also functions at the same time as a blocking or inhibiting element for the supplying of spray liquid to the spraying nozzle and at least one spring element is correlated to the respective cutter and operates the nozzle holder either in a spray liquid "open" or in a spray liquid "closed" position.
By virtue of the features of the present invention, the nozzle holder itself also functions as a shut off component and, consequently, it is no longer necessary to provide for any special shut off fittings or other shut off arrangements.
Moreover, by virtue of the features of the present invention, either the cutter or the shaft of the cutter controls the nozzle holder by virtue of the provision of at least one spring element such as, for example, a Belleville spring washer, whereby the nozzle holder can be used as an element for transferring the movements of the cutter when being subjected to stresses due to the cutting operation which are transferred by the spring element to the nozzle carrier which is then controlled in dependence upon the stresses developing during the cutting operation.
Advantageously, the spring element of the present invention may, for example, be disposed beneath a shoulder of a shaft of the cutter or a portion of the cutter itself and, all that is required is a relatively sturdy commercially available component such as a Belleville spring washer which is utilized as a transfer mechanism between the cutter and the nozzle holder to, for example, cause the nozzle holder to open when, for example, a rock or some other material is contacted thereby enabling the spraying of the spray liquid to reach the spraying nozzle.
In accordance with further advantageous features of the present invention, the spray duct accommodating the spraying liquid is connected by way of, for example, a triangular shaped flow chamber along an axial longitudinal section which extends in parallel to the longitudinal axis of the nozzle holder to which the spraying nozzle is connected in such a manner so as to enable liquid to flow therethrough.
By virtue of a provision of a triangular flow chamber and the above noted additional features, a relatively small tilting movement of the nozzle holder results in a relatively large free somewhat triangularly shaped chamber so that the spray fluid can flow in a very quick manner and, for all practical purposes, instantaneously, through a longitudinal duct of the nozzle holder up to the spray nozzle itself.
The nozzle holder may, in accordance with the present invention, be pivotally mounted so that it is possible to enable the nozzle holder to react or reset to a resetting force of at least one spring element. By virtue of these features, it is ensured that the resetting o the nozzle holder, namely, the returning to the closed position, occurs by the spring element after the forces have ceased to act upon the respective cutter.
Advantageously, according to the present invention, the spring element such as, for example, a Belleville spring washer, is adapted to be brought into abutting engagement against a shoulder of the cutter and changes its diameter when forces act on the cutter thereby tilting the nozzle holder in an opening direction movement while being supported on a sealing face of a valve seat.
Accordingly, it is an object of the present invention to provide a cutter roller equipped with spraying nozzles which avoids, by simple means, shortcomings and disadvantages encountered in the prior art.
Another object of the present invention resides in providing a cutter roller with spraying nozzles which is sturdy, lightweight, and utilizes individual components which can be manufactured at a reasonable cost.
A still further object of the present invention resides in providing a cutter roller with spraying nozzles which is adapted to rough working conditions to which cutter rollers are subject and, in particular, to cutting conditions which occur in underground coal mining.
These and other objects, features, and advantages of the present invention will become more apparent from the following description when taken in connection with the accompanying drawings which show, for the purposes of illustration only, one embodiment in accordance with the present invention .